Presently, many though not all of the arithmetic operations that OpenSSL
provides are exposed to Perl via Crypt::OpenSSL::Bignum. In addition, this
module can be used to provide access to bignum values produced by other
OpenSSL modules, such as key parameters from Crypt::OpenSSL::RSA.

/usr/share/doc/libcrypt-openssl-bignum-perl/README

Crypt::OpenSSL::Bignum is an XS perl module designed to provide basic
access to the OpenSSL multiprecision integer arithmetic libraries.
Presently, many though not all of the arithmetic operations that
OpenSSL provides are exposed to perl. In addition, this module can be
used to provide access to bignum values produced by other OpenSSL
modules, such as key parameters from Crypt::OpenSSL::RSA. Th
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